Observasi geomorfologi dan pola aliran sungai daerah Bentarsari dan sekitarnya, Jawa Tengah

Abstract

The Bentarsari area is administratively located in Salem District, Brebes Regency, Central Java. The Bentarsari area in general has hilly conditions. Based on the Geological Map of the Majenang Sheet, this area comprises Tertiary breccias, sandstones, and claystone. The purpose of this study was to determine the geometry and shape of the earth's surface such as height, area, slope, rock lithology, river density, river flow patterns, and river valley shapes. Geomorphological conditions were carried out in the form of topographic map analysis with a scale of 1: 12.500, Shuttle Radar Image Topography Mission, and direct field observations. The study area is divided into three geomorphological units, the first being the Ganggawang Homocline Hills Unit composed of sandstone and breccia lithology, the genetic type of successive and consequent rivers with dendritic flow river patterns, and the shape of the V river valley. The second geomorphological unit is the Bentarsari Structural Hills Unit composed of lithology sandstone and claystone, obsequent, subsequent, and consequent river genetic types with dendritic river flow patterns, V, U shape of river valleys. Finally, the Alluvial Plain Unit is composed of loose material consisting of igneous rock and sedimentary rock ranging in size from fine sand to lumps.